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arXiv · 1112.2041

The Extremely High-Velocity Outflow from the Luminous Young Stellar Object G5.89-0.39

Yu-Nung Su·Sheng-Yuan Liu·Huei-Ru Chen·Ya-Wen Tang
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Abstract

We have imaged the extremely high-velocity outflowing gas in CO (2-1) and (3-2) associated with the shell-like ultracompact HII region G5.89-0.39 at a resolution of ~3" (corresponding to ~4000 AU) with the Submillimeter Array. The integrated high-velocity (>45 km/s) CO emission reveals at least three blueshifted lobes and two redshifted lobes. These lobes belong to two outflows, one oriented N-S, the other NW-SE. The NW-SE outflow is likely identical to the previously detected Br_gamma outflow. Furthermore, these outflow lobes all clearly show a Hubble-like kinematic structure. For the first time, we estimate the temperature of the outflowing gas as a function of velocity with the large velocity gradient calculations. Our results reveal a clear increasing trend of temperature with gas velocity. The observational features of the extremely high-velocity gas associated with G5.89-0.39 qualitatively favor the jet-driven bow shock model.

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Yu-Nung Su, Sheng-Yuan Liu, Huei-Ru Chen, Ya-Wen Tang. 2011-12-09. The Extremely High-Velocity Outflow from the Luminous Young Stellar Object G5.89-0.39. https://doi.org/10.1088/2041-8205%2F744%2F2%2Fl26

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